JPH06327261A - Power device - Google Patents

Abstract

PURPOSE:To make the efficiency higher, to prevent the occurrence of other hindrances, and to make load current constant regardless of the conditions of the load and the increase or decrease of the number of the load, concerning a power device which receives current from a high-frequency power source with a plurality of current transformers and operates the load with respective current transformers. CONSTITUTION:A high-frequency power source is composed of a DC voltage converting part 3 for converting a DC voltage to an arbitrary voltage value by switching operation, an inverter part 4 for converting the DC voltage converted by the DC voltage converting part 3 to a high-frequency voltage by switching operation, and an output current detecting part for detecting the output current of the inverter part 4. And the output current of the inverter part 4 is made constant by controlling the switching operation of at least one of the DC voltage converting part 3 and the inverter part 4 by the detected output of the output current detecting part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device in which a current supplied from a high frequency power supply is received by a plurality of current transformers and a load is operated by each of the current transformers.

[0002]

2. Description of the Related Art FIG. 21 shows a conventional example of a lighting system using a high frequency power source and a current transformer (Actual development number: 59-46496).
No.). In the figure, B ₁ , B ₂ and B ₃ are lighting fixtures, which are dispersed and installed at locations away from the power source. This lighting system is provided with a constant current high frequency power supply A that inputs a commercial power supply Vs and outputs a high frequency constant current, and its output current I is one of a plurality of current transformers T ₁ , T ₂ , T ₃ .
It is supplied to the next winding. Each current transformer T ₁ , T ₂ ,
Fluorescent lamps FL ₁ , FL ₂ and F are provided on the secondary windings of T ₃ , respectively.
A lighting load such as L ₃ is connected. The primary winding of each current transformer T ₁ , T ₂ , T ₃ is a single wire, and this wire is inserted into an iron core forming a closed magnetic circuit such as a toroidal core to perform one turn of magnetic coupling. And
A load current is supplied from the secondary winding wound around the iron core. Here, the constant-current high-frequency power source is not clearly shown in Japanese Utility Model Publication No. 59-46496,
A power amplifier is generally conceivable as a means for realizing this. However, in the case of the power amplifier, although it is considered that the output can be easily applied to the circuit of FIG. 21, in order to amplify the power of the reference signal output from the high-frequency oscillator, the output power from the power amplifier is The input power supplied to the power amplifier becomes extremely large, which is not practically preferable in terms of efficiency.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to receive a current supplied from a high frequency power source by a plurality of current transformers, and to receive the currents respectively. It is an object of the present invention to provide a power supply device in which a load is operated by the current transformer, the power supply device having high efficiency and no other trouble. Another object of the present invention is to provide a power supply device in which the load current is constant with respect to the load state and the increase / decrease in the number.

[0004]

According to the present invention, the above
In order to solve the problem, as shown in FIG.
Frequency constant current output from the frequency power supply A
Lance T₁ , T₂ , T ₃ Supply to each primary winding of
Transformer T₁ , T₂ , T₃ Load connected to the secondary winding of
FL₁ , FL₂ , FL₃ Power supply that operates the high frequency
In FIG. 1, the high frequency power source A is, for example, as shown in FIG.
As the DC voltage is switched to an arbitrary voltage
DC voltage conversion unit 3 for converting into a value and DC voltage conversion unit 3
Higher DC voltage converted by switching operation
An inverter unit 4 for converting into a frequency voltage, and an inverter unit 4
Of the output current of the DC voltage converter 3 and the inverter
Controls the switching operation of at least one of the switching units 4.
To make the output current of the inverter unit 4 constant by
And an output current detector 6 of
is there.

[0005]

According to the present invention, the current detecting section 6 is provided at the output of the inverter section 4 for converting the DC voltage output from the DC voltage converting section 3 into a high frequency voltage by a switching operation,
Even if the state of the load 5 changes, the operating conditions of the DC voltage converter 3 or the inverter unit 4 are controlled so that the output current is kept constant. Can be controlled to be constant, and the efficiency is improved as compared with the case where a power amplifier is used. The more detailed structure and operation of the present invention will be more apparent in the following description of the embodiments.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an embodiment of the invention according to claim 1 or 2.
It is a circuit diagram of. The circuit configuration is explained in detail below.
Reveal The commercial power supply Vs is full-wave via the noise prevention circuit 1.
It is connected to the AC input terminal of the rectifier circuit 2. This noise
The prevention circuit 1 includes a capacitor C₁ , C₂ And chalk carp
Le L₁ A low-pass filter is configured with to reduce power supply feedback noise.
It also reduces the input current distortion. Full-wave rectification
The step-down chopper circuit 3 is connected to the DC output terminal of the circuit 2.
Has been continued. At the input terminal of the step-down chopper circuit 3,
MOS transistor Q for switching₁ And energy
-Inductor L for storage₂ And a smoothing capacitor C_Four 
The series circuit of is connected. Inductor L₂ And Conde
Sensor C_Four The series circuit of the
Mode D ₁ Are connected with the polarities shown. C₃ Is high
This is a capacitor for frequency bypass, and it is a step-down chopper circuit.
It is connected in parallel to the input terminal of path 3. MOS transistor
Star Q₁ Is turned on at a high frequency by the chopper control circuit 31.
N / OFF. MOS transistor Q₁ Is turned on
Then, from the full-wave rectifier circuit 2 to the MOS transistor Q ₁ ,I
Inductor L₂ , Capacitor C_Four Current flows through
Inductor L₂ Energy is stored in. MOS Tiger
Register Q₁ Is turned off, inductor L₂ Both ends of
Voltage is generated in the capacitor C_Four , Diode D₁ Through
Then, current flows and inductor L₂ The energy of
Densa C_Four Is released to. As a result, the capacitor C_Four 
A smooth DC voltage is obtained at.

The output of the step-down chopper circuit 3 has an inverter
Data circuit 4 is connected. The inverter circuit 4 is M
OS transistor Q₂ , Q₃ Series circuit and MOS transistor
Dista Q_Four , Q_Five Series circuit is connected in parallel to the input side
There is. MOS transistor Q ₂ , Q₃ Connection point and MOS
Transistor Q_Four , Q_Five Between the connection points of the inductor
L₃ And capacitor C_Five Connected to the series resonance circuit
It Capacitor C_Five At both ends of the isolation transformer Tf 1
The secondary winding is connected in parallel. Secondary of isolation transformer Tf
The winding has a capacitor C₆ , C₇ And transformer L_Four More
Sine wave filter circuit is connected. Inverter times
The output of the path 4 is sent to the load 5 via the current detection transformer CT.
Is being supplied. Both output windings of current detection transformer CT
The end is diode D₂ , D₃ To the current detection circuit 6 via
The center tap of the output winding is grounded.
Has been. The output of the current detection circuit 6 is the output of the differential amplifier circuit 7.
This is the first input. Second input of differential amplifier circuit 7
Is a constant voltage Vcc ₁ And the variable resistor VR
The reference voltage is input. Output of differential amplifier circuit 7
Is fed back to the chopper control circuit 31.
It MOS transistor Q₂ ~ Q_Five Inverter control times
ON / OFF control is performed by the output of the path 41. Inver
The controller control circuit 41 divides the frequency of the output of the oscillator circuit 42,
S transistor Q ₂ , Q_Five Is ON, MOS transistor
Q₃ , Q_Four And the first state where the
Dista Q₂ , Q_Five OFF, MOS transistor Q₃ ，
Q_Four So that it alternates with the second state in which
S transistor Q₂ ~ Q_Five To control. Full wave rectifier circuit 2
The AC input terminal of the diode D_Four , D_Five Through the
The soft start circuit 8 is connected. Soft start
The output of the circuit 8 is input to the chopper control circuit 31.
There is.

The operation of this embodiment will be described below.
In the present embodiment, the AC voltage from the commercial power supply Vs is rectified by the full-wave rectifier circuit 2, converted into a smooth DC voltage by the step-down chopper circuit 3, and converted into high-frequency power by the inverter circuit 4 in the subsequent stage bridge configuration. Load 5
Is being supplied to. The step-down chopper circuit 3 obtains a DC voltage lower than the full-wave rectified commercial voltage by the switching operation of the MOS transistor Q ₁ , the inductor L ₂ for storing energy, the smoothing capacitor C _{4, and the} like. . When the power is turned on, the soft start circuit 8
Thus, the on-duty of the MOS transistor Q ₁ is suppressed and gradually expanded to suppress the inrush current. Normally, the load current is detected by the current transformer CT which is connected in series with the load 5, and the voltage corresponding to the magnitude of the load current is compared with the reference voltage, and the MOS transistor Q ₁
By changing the duty of, the output voltage of the step-down chopper circuit 3 is changed so that the load current becomes constant.

The inverter circuit 4 constitutes a full bridge circuit with the MOS transistors Q _{2 to} Q ₅ , and the oscillation circuit 42
The frequency determined by is divided by the inverter control circuit 41,
The MOS transistors Q ₂ , Q ₅ and Q ₃ , Q ₄ are alternately switched. The switching frequency is an arbitrary value in the range of approximately 40 kHz to 100 kHz. The output voltage of a full-bridge inverter is a rectangular wave, but a sine wave filter circuit mainly composed of a series resonance circuit of an inductor L ₃ and a capacitor C ₅ and an insulating transformer Tf, capacitors C ₆ , C ₇ , an inductor L _4, etc. Outputs a current close to a sine wave. This has a waveform close to a sine wave in order to minimize the radiation noise generated from the wiring path when the high-frequency current is supplied to the load. Further, the output of the inverter circuit 4 is insulated by the insulating transformer Tf in order to prevent the risk of electric shock during construction, reduce the leakage current to the ground, and reduce the wiring loss due to it. .

In this embodiment, the step-down chopper circuit 3 and the inverter circuit 4 perform the conversion into the DC voltage and the high frequency power by the switching elements, and the conversion efficiency is much higher than the case where the power amplifier is used, and the size is reduced. And contribute to the effective use of resources. Also, in order to make the load current constant,
Since the output voltage of the step-down chopper circuit 3 is changed, stable operation can be obtained with a simple configuration. Furthermore, the oscillation frequency of the inverter circuit 4 is 40 kHz.
Since it is fixed to an arbitrary value within the range of z to 100 kHz and the waveform is close to a sine wave, it is advantageous because noise countermeasures can be limited to a specific frequency and the waveform does not contain harmonic components. The load current is output via the insulating transformer Tf, so that danger such as electric shock can be prevented and wiring loss can be reduced. Further, since the input voltage is once lowered by the step-down chopper circuit 3 and the inverter circuit 4 is operated, the withstand voltage of the switching element used in the inverter circuit 4 can be lowered, and the switching element having a small ON resistance is correspondingly reduced. Can be used, and the conversion efficiency can be further improved.

FIG. 2 is a circuit diagram of another embodiment of the invention described in claim 1. In this embodiment, a buck-boost chopper is used as the chopper circuit 3, and a push-pull circuit is used as the inverter circuit 4. First, the operation of the buck-boost chopper circuit 3 will be described. When the MOS transistor Q ₁ is turned on, the inductor L is fed from the DC output terminal of the full-wave rectifier circuit 2 via the MOS transistor Q _1.
A current flows through ₂ and energy is stored in the inductor L ₂ . When the MOS transistor Q ₁ is turned off, the energy accumulated in the inductor L ₂ causes electromotive force to be generated across the inductor L ₂ and the diode D ₁
The capacitor C ₄ is charged via the. In this embodiment, the energy stored in the inductor L ₂ is changed by changing the duty of the MOS transistor Q ₁ to boost the output voltage of the step-up / down chopper circuit 3 (voltage of the capacitor C ₄ ) with respect to the power supply voltage. It is also designed to be able to reduce the voltage. Next, the operation of the inverter circuit 4 will be described. In this embodiment, a self-exciting push-pull inverter is used, and a magnetic leakage type isolation transformer T is used.
By providing a feedback winding at f, the transistor Q ₂ ,
The Q ₃ alternately is intended to be turned on and off. Note that the capacitor C ₅ is connected for resonance, and is voltage-resonated by the insulating transformer Tf and the capacitor C ₅ . Therefore, the output current has a waveform close to a sine wave.

In this embodiment, the buck-boost chopper circuit 3
Since, for example, the power supply voltage is 100 V and 20
Output voltage is about 150V so that it can be used for both 0V
As the design is centered on the degree, it can easily correspond to the power supply voltage. Further, since the inverter circuit 4 is a resonance type self-excited inverter, the switching loss is small and the waveform distortion is small, which is advantageous in terms of noise suppression and the circuit structure is simple.

The DC voltage converter in the first aspect of the invention is not limited to the step-down chopper or the step-up / step-down chopper, and any step-up chopper or the like that converts a DC voltage by a switching operation can be used. Can be used. Further, the configuration of the inverter unit that converts the DC voltage into the high frequency voltage is not limited to the bridge type or the push-pull type, and any configuration that converts the DC voltage into the high frequency voltage by the switching operation such as the one-stone type or the half bridge type can be used. Any method can be used.

FIG. 3 is a circuit diagram showing an embodiment of the invention described in claim 4. The circuit configuration will be described below. The commercial power supply Vs is connected to the AC input terminal of the full-wave rectifier circuit 2 via the noise prevention circuit 1. A smoothing capacitor C ₄ is connected to the DC output terminal of the full-wave rectifier circuit 2. A series circuit of MOS transistors Q ₁ and Q ₂ is connected in parallel to both ends of the capacitor C ₄ . M
At both ends of the OS transistor Q ₁ , an inductor L ₃ and a capacitor C ₃ are provided via a coupling capacitor Cc.
₅ series resonant circuits are connected. A primary winding of an insulating transformer Tf is connected in parallel to both ends of the capacitor C ₅ . The output current from the secondary winding of the isolation transformer Tf is supplied to the load 5 via the current detection transformer CT. Both ends of the output winding of the current detection transformer CT are input to the current detection circuit 6 via the diodes D ₂ and D _3, and the center tap of the output winding is grounded.
The output of the current detection circuit 6 is the first input of the comparison circuit 9. The second input of the comparator circuit 9 is connected to the oscillator OSC.
A signal obtained by converting the rectangular wave signal of 1 to a triangular wave by the integrating circuit 10 is input. The output of the comparison circuit 9 is fed back to the inverter control circuit 41. The MOS transistors Q ₁ and Q ₂ are ON / OFF controlled by the output of the inverter control circuit 41. Inverter control circuit 41
Inverts the output of the comparison circuit 9 by the NOT circuit NT,
_The voltage is supplied to the gate of the high potential side MOS transistor Q ₁ via a drive circuit composed of ₈ , R ₁₀ , transistors Q ₁₀ , Q ₁₁ , Q ₁₂ and a driving transformer Td and a capacitor C _10, and at the same time, a resistor R ₂₀ , a transistor Q It is supplied to the gate of the MOS transistor Q ₂ on the low potential side through a drive circuit composed of ₂₀ , Q ₂₁ , and Q ₂₂ .

The operation of this embodiment will be described below.
In this embodiment, as a high frequency power source for driving the load
A series inverter is used and its switching element
Child duty (that is, the ratio of the on period to the off period)
To stabilize the output current to the load by changing
It is something. MOS transistor of inverter circuit 4
Q₁ , Q₂ Is the control signal from the inverter control circuit 41
Therefore, they are alternately turned on and off. First, MOS transistor
Star Q₁ Is off, MOS transistor Q ₂ Is ON
When the condition is reached, the capacitor C_Four For coupling
Capacitor Cc, capacitor C_Five And insulation transformer Tf 1
Next winding, inductor L₃ , MOS transistor Q₂ Through
Then, the current flows and the charge is accumulated in the capacitor Cc.
It Next, the MOS transistor Q₁ Is ON, MOS
Transistor Q₂ Is turned off, the capacitor C
c is the power source, and the MOS transistor Q₁ , Inductor
L₃, Capacitor C_Five And the primary winding of the isolation transformer Tf
Current flows in the opposite direction. As a result, the isolation transformer Tf
High-frequency current is output from the secondary winding of the
Supply. Insert current detection transformer CT in series with load 5.
Turn on and generate in the output winding of this current detection transformer CT
Voltage to diode D₂ , D₃ Full-wave rectification by
₃ , R_Four And capacitor C₈ Consists of a CR integration circuit consisting of
It is averaged by the current detection circuit 6
A voltage signal is generated and used as a first input of the comparison circuit 9.
And On the other hand, the oscillation frequency of the inverter circuit 4 is determined
The square wave signal of the oscillator OSC is applied to the resistor R_Five And capacitor C₉ 
Is converted into a triangular wave by the integration circuit 10 composed of
The second input of the comparator circuit 9. This allows the comparison circuit
The signal output from 9 is the oscillation frequency of the oscillator OSC.
They have the same frequency and are
It becomes a signal that changes the tee.
Register Q₁ , Q₂ Is turned on and off alternately. load
If the current is higher than necessary, the MOS transistor Q₂ of
MOS transistor Q during the off period₁ Longer than the off period
By suppressing the output of the inverter circuit 4,
The load current is made constant.

FIG. 4 shows another embodiment of the invention according to claim 4.
It is a main part circuit diagram. In this example, the bridge type inverter
A DC transistor is used for the DC power supply E.
Q₂, Q₃ Series circuit and MOS transistor Q_Four , Q_Five
 Series circuits are connected in parallel. MOS Transis
Q₂ , Q₃ Connection point and MOS transistor Q_Four , Q _Five 
The primary winding of the isolation transformer Tf is connected between the connection points of
Has been done. MOS transistor Q₂ , Q_Five Is ON
Then, the MOS transistor Q₃ , Q_Four Is off
Sometimes the primary winding of the isolation transformer Tf is unidirectional
Flows, the MOS transistor Q₃ , Q_Four Is ON,
MOS transistor Q₂ , Q_Five Is off
Current flows in the reverse direction to the primary winding of the isolation transformer Tf.
Be done. As a result, the secondary winding of the isolation transformer Tf has a high
The frequency current is output and supplied to the load. Output current detection
The configuration of the circuit and the like is similar to that of the embodiment shown in FIG. Fruit of Figure 3
In the example, a series inverter is used to reduce the load current.
Depending on the MOS transistor Q₁ , Q₂ ON / OFF data
The output is kept constant by changing the duty ratio.
In the embodiment, as shown in FIGS.
Langista Q₂ , Q _Four The duty and frequency of
However, if the load current is excessive, the MOS transistor
Q_Five , Q₃ By narrowing the on-duty of
The output is suppressed. Figure 5 (a) is the maximum
MOS transistor Q at high output₂ ~ Q_Five Shows the behavior of
FIG. 5B shows a MOS transistor when the output is suppressed.
Q₂ ~ Q_Five Shows the operation of.

In the embodiment of FIG. 3 or 4, an example in which the on / off duty of the switching element is changed to make the output current constant has been described. However, for example, the oscillation frequency is changed to make the output constant. The same can be applied to what is made. The basic circuit configuration of the inverter is not limited to the serial type or the bridge type, and the configuration is not limited to the half bridge type, for example.

By the way, in the embodiment of FIG. 1 or FIG.
When the lamp is started by changing the output voltage of the chopper circuit 3
When the load fluctuates, such as at the end of life, at the end of life, or when a load is added.
Changes in the output current of the inverter circuit 4 are detected.
Switching operation of the chopper circuit 3 according to the detection result of
DC power supplied to the inverter circuit 4 by changing the operation
The pressure E is changed to keep the output current constant.
A smoothing capacitor C is provided at the output end of the chopper circuit 3._Four But
Since it is connected, switching of the chopper circuit 3
Even if the operation is changed, the output voltage of the inverter circuit 4 is instantaneously changed.
Sometimes it is difficult to change. So when responding
If the interval exceeds 10 msec, for example,
As shown in, the fluorescent lamp F connected to the same high frequency power source
L₁ , FL₂ , FL₃ Light output fluctuates, flicker, etc.
May occur. On the other hand, in the embodiment of FIG. 3 or FIG.
Is a power supply smoothing capacitor for instantaneous load changes.
SA C _Four The response time is short because it can be controlled regardless of
Wear. However, the control conditions of the inverter circuit 4 and waveform shaping
The output current waveform may be a harmonic
There may be a distorted waveform containing many components. Of FIG.
The lighting system includes a high frequency power supply A and a lighting fixture B.₁, B₂，
B₃Since they are used separately, high-frequency currents
Radiation noise generated from the wiring path may interfere with other equipment.
It is possible that

Therefore, in order to reduce the response time to the load fluctuation and to minimize the noise disturbance, the switching operation of the chopper circuit 3 is controlled for the load fluctuation for a relatively long time, and the relatively short time. It is conceivable to control the switching operation of the inverter circuit 4 with respect to the load fluctuation of. An example thereof is shown in FIG. In this embodiment, the buck-boost chopper circuit 3 and the half-bridge type inverter circuit 4 constitute a high frequency power source. First,
In the step-up / down chopper circuit 3, the load on the switching element is reduced by using two MOS transistors Q ₀ and Q ₁ . The chopper circuit 3 is controlled by the soft start circuit 8 when the power is turned on, and suppresses the inrush current.
Further, except when the power is turned on, the output current from the inverter circuit 4 is detected by the current detection transformer CT, and the first time constant circuit CR ₁ performs feedback control with a signal averaged with a relatively large time constant. Thereby, the output voltage of the chopper circuit 3 is changed according to the detected current, and the output current is controlled to be constant. Also,
The detection signal of the current detection transformer CT is averaged by the second time constant circuit CR ₂ with a relatively small time constant, and input to the oscillation circuit 42 of the inverter circuit 4. The oscillating circuit 42 changes the oscillating frequency of the inverter circuit 4 so that the output current becomes constant with respect to a load change for a relatively short time, and as a result, it may be felt by the afterimage effect of human eyes. Flicker that is impossible (10m
It is possible to respond to load current fluctuations of sec or less) and no discomfort occurs. Further, in order to constantly set the control condition of the inverter so that the output waveform has the least distortion, the output of the first time constant circuit CR ₁ is corrected by the correction circuit 43.
Is input to the oscillation circuit 42 via. This allows
It is possible to minimize the noise continuously generated from the wiring path. The correction circuit 43 corrects the control condition of the inverter according to the chopper output voltage so that the oscillation frequency and the duty are convenient for noise removal. The noise level rises for an extremely short time before the steady state is entered, but a state that is practically unproblematic can be achieved.

The chopper circuit 3 provided in the preceding stage of the inverter circuit 4 is not limited to the step-up / down type, but may be, for example, a step-up type or a step-down type. The inverter circuit 4 is not limited to the half bridge type, but may be a full bridge type, and any method can be used as long as its steady output waveform is close to a sine wave. Further, as the output control method of the inverter circuit 4, the method of changing the frequency is shown.
A method of changing the duty of the switching element may be used.

By the way, in the lighting system using the high frequency constant current power supply shown in FIG. 21, the electric wire wired to each lighting fixture is, for example, at the place where the lighting fixture B ₁ is arranged as shown in FIG. Since one wire runs through the current transformer T ₁ and it is a high frequency current, the wire used is one core of the twisted wire as shown in FIG. 8 in order to avoid an increase in resistance due to the skin effect. I am using one. For indoor wiring to a lighting device such as a ceiling of a general commercial power source, as shown in FIG. 9, a two-core or three-core VVF wire is rolled and wired on the back of the ceiling. The cross-sectional structure of the VVF line used for the commercial power source is close as shown in FIG. 10, but the output wiring from the high frequency power source is not close as shown in FIG.
In the wiring state as shown in FIG. 7, as shown in FIG. 11, the loop area S surrounded by the current I flowing through the wiring becomes large. As is generally said, the level En of noise radiated from a wiring is proportional to the loop area S surrounded by the output wiring, the flowing current I, and the square of its frequency f. . Therefore, the noise level En ∝S
In order to reduce If ² , the respective terms S, I, and f may be reduced, but the current I needs to have a constant value in order to keep the discharge lamp or the incandescent lamp of the load lit, and the current I must be small. Loop area S and frequency f
Is the target. Further, in order to reduce the noise, there is also a method of not only reducing the noise level itself but not leaving it outside.

Therefore, a configuration for reducing noise from the output wiring will be described. First, FIG. 12 shows a method of reducing the loop area S, in which both reciprocating wires of the output wiring W are arranged close to each other and fixed with a clip jig J at a constant line length so as not to be separated from each other by a predetermined distance or more. ing. Here, as the clip jig J, an E-shaped one as shown in FIG.
An arbitrary shape such as a spiral shape shown in FIG. 14 can be used. Further, as shown in FIG. 15, there is also a method in which both the reciprocating wires of the output wire W are housed in a tubular tube except for the parts to which the current transformers T ₁ and T _{2 serving} as loads are connected. The conduit 12 may be made of metal or resin, but if punching metal is used, radiation of electromagnetic waves can be prevented and the weight can be reduced. In the embodiment using the clip jig shown in FIG. 12, since the output wiring is free between the clip jigs, the distance between the lines may be wide, and it is difficult to limit the loop area S. In the fifteenth embodiment, the distance between lines is suppressed to be equal to or smaller than the diameter of the pipe. The tube may be split in two along the central axis.

Instead of the tube in the embodiment of FIG. 15, as shown in the embodiment of FIG.
You may pass both round-trip lines in 3. This wire 13
Does not have to be metal. In the embodiment of FIG. 15, the pipe cannot be bent, so that the workability is poor, but in the embodiment of FIG. 16, since the spiral wire can be bent, the workability is improved. Next, in the embodiment shown in FIG. 17, both reciprocating lines of the output wiring are formed by twisted pair wires Wtp. A jig is required in each of the embodiments of FIGS. 12 to 16, but a jig is not necessary in the embodiment of FIG. 17 using this twisted pair wire.

Next, a structure for removing high-order frequency components of the output wiring will be described. In the embodiment shown in FIG. 18, a ferrite ring core 14 is attached to the roots of both output terminals of the constant current high frequency power supply A. Although the inductance L due to the ring core 14 is small, its impedance ωL changes depending on the oscillation frequency and becomes a large impedance with respect to high-order frequency components, so that high-order frequency components do not easily flow to the load side. Also, FIG.
In the embodiment shown in FIG. 9, a series circuit of two capacitors Ca and Cb is inserted between both output terminals of the constant current high frequency power supply A. The electrostatic capacitance C of the capacitors Ca and Cb is set to have a relationship of 1 / ωC >> ωL with respect to the inductance L of the output wiring. Then, the potential at the connection point of the capacitors Ca and Cb is connected to the shield wire Ws along the output wire W. As a result, as shown in the equivalent circuit of FIG. 20, since the wiring capacitance Cs between the output wiring W and the shield line Ws is larger than the capacitance Ce between the output wiring W and the ground, high frequency power (noise) is generated. Flows from the noise source Vn of the output wire W to the noise source Vn through the shield wire Ws via the wire capacitance Cs between the output wire W and the shield wire Ws. Therefore, since noise does not escape to the outside, the noise level is reduced and the efficiency is improved.

[0025]

According to the invention described in claim 1, a plurality of current transformers receive the current supplied from the high frequency power source,
In a power supply device in which a load is operated by each current transformer, a DC voltage conversion unit that converts a DC voltage into an arbitrary voltage value by a switching operation, and a DC voltage converted by the DC voltage conversion unit by a switching operation to a high frequency A high-frequency power supply is composed of an inverter unit that converts the voltage and an output current detection unit that detects the output current of the inverter unit, and the switching output of at least one of the DC voltage conversion unit and the inverter unit is detected by the output output of the output current detection unit. Since the output current of the inverter unit is controlled to be constant by control, there is an advantage that the conversion efficiency as a power source is high, and it is possible to supply power more efficiently than when using a power amplifier. There is.

According to the second aspect of the present invention, the DC voltage output from the DC voltage conversion unit is converted into a high frequency by the inverter unit and is supplied to the load through the plurality of current transformers. In the above, since the voltage of the DC voltage conversion unit is changed so that the output current becomes constant, the inverter unit may operate under the same oscillation condition even if the input voltage changes, which is complicated. There is an advantage that control is unnecessary and the configuration is simple.

According to the third or fourth aspect of the invention, in the power supply device in which the DC voltage is converted into a high frequency by the inverter unit and is supplied to the load through the plurality of current transformers, the output current becomes constant. As described above, since the duty and frequency of the switching element in the inverter unit are changed, the load current can be made constant even if the load current changes depending on the load state or number.
There are advantages that the efficiency is higher than that when a power amplifier is used and that stable operation can be realized as compared with the case where output is controlled by intermittent burst oscillation operation.

According to the fifth aspect of the invention, since the switching operation of the inverter is changed in response to a temporary load change, it is possible to eliminate the flicker that human eyes perceive. Since the switching operation of the DC voltage converter is changed in response to long-term load fluctuations, the inverter can be operated under control conditions that are advantageous for noise countermeasures, and the electromagnetic waves radiated from the output wiring can be operated. There is an effect that noise can be reduced.

According to the sixth aspect of the invention, since the waveform shaping section for shaping the output current into a current close to a sine wave is provided,
Since noise countermeasures can be limited to specific frequencies and the waveform does not contain many harmonic components, there is an effect that noise can be significantly reduced.

According to the invention described in claims 7 to 12,
High-frequency current flows by reducing the loop area through which high-frequency current flows, by suppressing the high-frequency current that exceeds the fundamental wave component from flowing through the output wiring, or by making it difficult for high-frequency current to flow between the output wiring and ground. There is an effect that noise radiated from the output wiring can be reduced.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an embodiment of the invention described in claim 1.

FIG. 2 is a circuit diagram of another embodiment of the invention according to claim 1;

FIG. 3 is a circuit diagram of an embodiment of the invention described in claim 4.

FIG. 4 is a circuit diagram of another embodiment of the invention according to claim 4;

FIG. 5 is an operation waveform diagram of another embodiment of the invention according to claim 4;

FIG. 6 is a circuit diagram of an embodiment of the invention described in claim 5.

FIG. 7 is a cross-sectional view showing a state of high-frequency wiring in the back of the ceiling of the present invention.

FIG. 8 is a cross-sectional view of a high frequency wiring used in the present invention.

FIG. 9 is a cross-sectional view showing a state of conventional commercial wiring on the ceiling.

FIG. 10 is a cross-sectional view of a commercial wiring used in a conventional example.

FIG. 11 is an explanatory diagram showing the principle of noise radiation by the high-frequency wiring of the present invention.

FIG. 12 is a circuit diagram showing a configuration of an invention according to claim 7;

FIG. 13 is a perspective view showing an example of a clip jig used in the invention according to claim 7;

FIG. 14 is a perspective view showing another example of the clip jig used in the invention according to claim 7;

FIG. 15 is a circuit diagram showing a configuration of an invention according to claim 10;

FIG. 16 is a circuit diagram showing a configuration of an invention according to claim 10;

FIG. 17 is a circuit diagram showing a configuration of an invention according to claim 8;

FIG. 18 is a circuit diagram showing a configuration of an invention according to claim 9;

FIG. 19 is a circuit diagram showing a configuration of an invention according to claim 12;

FIG. 20 is an equivalent circuit diagram for explaining an operation of the invention according to claim 12;

FIG. 21 is a circuit diagram of a conventional example.

[Explanation of symbols]

 1 Noise prevention circuit 2 Full wave rectifier circuit 3 Chopper circuit 4 Inverter circuit 5 Load 6 Current detection circuit 7 Differential amplifier circuit

Claims (12)

[Claims] 1. A power supply device for supplying a high frequency constant current output from a high frequency power supply to each primary winding of a plurality of current transformers to operate a load connected to a secondary winding of each current transformer at a high frequency. The high-frequency power supply includes a direct-current voltage conversion unit that converts a direct-current voltage into an arbitrary voltage value by a switching operation, an inverter unit that converts the direct-current voltage converted by the direct-current voltage conversion unit into a high-frequency voltage by a switching operation, and an inverter unit. A power supply including an output current detection unit for detecting the output current of the inverter and controlling the switching operation of at least one of the DC voltage conversion unit and the inverter unit to make the output current of the inverter unit constant. apparatus. 2. The output current detection unit is means for detecting the output current of the inverter unit and changing the output voltage of the DC voltage conversion unit so as to make the output current of the inverter unit constant. The power supply device according to item 1. 3. The output current detection unit detects at least the output current of the inverter unit and keeps the output current of the inverter unit constant, at least one of the ratio of the ON period and the OFF period of the switching element in the inverter unit and the oscillation frequency. The power supply device according to claim 1, wherein the power supply device is means for changing 4. A power supply device for supplying a high frequency constant current output from a high frequency power supply to each primary winding of a plurality of current transformers to operate a load connected to a secondary winding of each current transformer at a high frequency. The high frequency power supply includes an inverter unit that converts a DC voltage into a high frequency voltage by a switching operation, and detects at least one of an ON period and an OFF period ratio and an oscillation frequency of a switching element in the inverter unit by detecting an output current of the inverter unit. A power supply device comprising: an output current detection unit for controlling the output current of the inverter unit by controlling the output current. 5. A power supply device for supplying a high frequency constant current output from a high frequency power supply to each primary winding of a plurality of current transformers to operate a load connected to a secondary winding of each current transformer at a high frequency. The high-frequency power supply includes a direct-current voltage conversion unit that converts a direct-current voltage into an arbitrary voltage value by a switching operation, an inverter unit that converts the direct-current voltage converted by the direct-current voltage conversion unit into a high-frequency voltage by a switching operation, and an inverter unit. Output current detecting unit for stabilizing the output current of the inverter unit by controlling the switching operation of the DC voltage converting unit and the inverter unit by detecting the output current of the Changes the switching operation of the inverter section, and changes the switching operation of the DC voltage conversion section for long-term load fluctuations. A power supply device characterized by being configured as described above. 6. The power supply device according to claim 1, wherein the high-frequency power supply has a waveform shaping section that shapes the output current into a current close to a sine wave. 7. A high frequency constant current power supply, and a closed loop output wiring to which a constant current output from the power supply is supplied,
In a power supply device including a current transformer having a magnetic core that passes through the output wiring as a primary winding and a lighting load connected to a secondary winding of the current transformer, two reciprocating wires of the output wiring are parallel to each other. A power supply device characterized by being brought close to. 8. The power supply device according to claim 7, wherein the output wiring is a twisted pair wire. 9. The power supply device according to claim 7, wherein a ring-shaped ferrite core is mounted for each output wiring near the output terminal of the output wiring from the high frequency constant current power supply. 10. The power supply device according to claim 7, wherein the power supply device has a plurality of the current transformers, and the output wirings wired between the respective power supply transformers are housed in a metal or non-metal conduit tube. 11. The power supply device according to claim 10, wherein the conduit is made of punching metal. 12. A capacitor is connected in series between the output terminals of the output line, and a shield line connected to the potential of the connection point is arranged in parallel with the output line. Item 7. The power supply device according to item 7.